Hi Sandra,
After some more troubleshooting, I noticed that if I disabled and re-enabled the NIC in Device Manager, it would be assigned an IP, but unable to communicate with the router.
I have resolved the problem by doing a CMOS reset - which seems a strange fix.
The only thing I can think of, is that because I hadn't used the NIC for about a month, that perhaps it went into some sort of power saving mode or something? Is this something that could of happened?
Regards,
Reece